1941 Oliver Row Crop 60 HC during test #375. Carlton Zink (in hat) on far left. The other two men are Oliver Reps. The tire is marked "Test K. "The tire that is on the rear of the tractor is marked Test F,G,H. They apparently changed tires...

Unidentified Oliver Tractor (possibly the Oliver 60) during a drawbar test. The Adams Test Car and a Massey Harris 55 load tractor are being towed on the dirt track adjacent to the old Tractor Test Lab building. Note the crankshaft revolution...

Title: "An early tractor test with a truck used as a load unit." An unidentifieds tractor on a dirt track towing the test car and a specially modified truck. Unfortunately there is no record of this type of load truck. Its towing resistance was...

Drawbar Test of Minneapolis Moline 12-25, Test # 13, 1920. The test car shown is the first one (the bathtub with a roof!) used. The interesting thing is the "fifth-wheel steer" system which must have made for difficult steering with the wide axle.

Deawbar test of Allis Chalmers "U". They use truck as load unit. No information available on the truck. Side view of the tractortowing the second test car and the load truck. This test was performed at Hoffmann Estates in Illinois

John Deere L drawbar test with the oldest NTTL test car and a load generating trailer. The two-wheeled load vehicle used a hydraulic pump and a valriable restriction to generate resistance on the trailer wheels. The resistance generated heat and...

Drawbar Test of John Deere L, Test#313, 1938. Tractor test on the dirt track. Th test car is the number 2 generation with the resistance trailer at the back. Apparently the Adams test car had a problem at the time.

"Checking the time clock on a John Deere tractor." Every tractor on test was provided with a mechanical time clock which recorded a time log of operating and stopping times during the test, This recording was made by a pen on a pressure sensitive...

"Test No. 394. Farm Veteran Trainees From Nebr. City, 1948. Recently a group of veterans taking the Institutional Farm Training at Nebraska City visited the Tractor Test Laboratory at the College of Agriculture. The 10 hour test was being...

"Test #. 402. Cylinder Head." Close-up of cylinder head from Centaur KV-48. This head was removed from the engine as part of the engine inspection which was carried out during the first 60-some years of the test procedure. It was done to insure...

"1948. Centaur KV 48, Test # 402. Changing drivers during 10 hour test." One man is climbing onto the tractor, which is in front of the tractor test car, while another man hops off the opposite side of the tractor. Two load tractors are behind...